Bicycle with battery mount

ABSTRACT

A bicycle including a frame, a bottom bracket coupled to the frame and adapted to support a crankset, and a battery pack supported by the frame. The battery pack has a powered end cap with a tapered protrusion and a battery connector on an end of the tapered protrusion. The bicycle also includes a receiver supported by the frame and including a tapered socket in which the tapered protrusion is positioned. The tapered socket includes a power connector detachably coupled to the battery connector.

BACKGROUND

The present invention relates generally to bicycles, and morespecifically to bicycles having an electric motor and battery.

Bicycles commonly have a main frame and a front fork pivotally securedto the main frame. The main frame typically includes a top tube, a downtube, a seat tube, and a rear wheel mount for receiving a rear wheelaxle. The front fork typically includes a front wheel mount forreceiving a front wheel axle. Steering control of the bicycle isprovided by a handlebar that is usually secured to the front fork via ahandlebar stem. Some bicycles also include a power source, such as abattery, to provide power to components on the bicycle, and in somecases, to provide motive power to the bicycle.

SUMMARY

The present invention provides a bicycle including a frame, a bottombracket coupled to the frame and adapted to support a crankset, and abattery pack supported by the frame. The battery pack has a powered endcap with a tapered protrusion and a battery connector on an end of thetapered protrusion. The bicycle also includes a receiver supported bythe frame and including a tapered socket in which the tapered protrusionis positioned. The tapered socket includes a power connector detachablycoupled to the battery connector.

In another aspect, the present invention provides a bicycle including aframe, a bottom bracket coupled to the frame and adapted to support acrankset, and a battery pack supported by the frame. The battery packincludes a securing end cap, and the bicycle further includes a contactplate that is supported by and movable relative to the frame. Thecontact plate includes a contact surface that is biased into contactwith the securing end cap.

In another aspect, the invention provides a bicycle including a frame, abottom bracket coupled to the frame and adapted to support a crankset,and battery pack supported by the frame, and a bottle cage mounted onthe battery pack.

Other aspects of the invention will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a bicycle including a frame embodying thepresent invention.

FIG. 2 is a perspective view of a portion of the frame including a downtube, a bottom bracket shell, and a battery pack.

FIG. 3 is an exploded perspective view of the down tube, the batterypack, the bottom bracket shell, a receiver, and a lock mechanism.

FIG. 4 is a rear perspective view of the bottom bracket shell with chainstays removed.

FIG. 5 is an exploded lower perspective view of the bottom bracket shellincluding an access opening and a door.

FIG. 6 is a section view of the down tube taken along line 6-6 in FIG.3.

FIG. 7 a is a section view of the frame taken along line 7-7 in FIG. 2.

FIG. 7 b is an enlarged view of a portion of the frame illustrated inFIG. 7 a.

FIG. 8 is a perspective view of an underside of the exterior of the downtube illustrating an exterior cable groove.

FIG. 9 is a perspective view of an interior of the down tubeillustrating interior cable grooves.

FIG. 10 is a perspective view of an upper area of the down tube with thebattery pack removed.

FIG. 11 is a perspective view of an upper end of the battery pack.

FIG. 12 is a side view of the upper end of the battery pack of FIG. 11.

FIG. 13 is a section view of a portion of the frame portion taken alongline 13-13 in FIG. 2.

FIG. 14 is a perspective view of a lower end of the battery pack.

FIG. 15 is a side view of the lower end of the battery pack.

FIG. 16 is a perspective view of a lower end of the frame with thebattery pack removed.

FIG. 17 is a perspective view of the lock mechanism.

FIG. 18 is a section view through a spring-biased latch of the lockmechanism of FIG. 17.

FIG. 19 is a section view of a lower part of the frame taken along line19-19 of FIG. 2.

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways.

DETAILED DESCRIPTION

FIG. 1 shows a bicycle 10 that includes a front wheel 15, a rear wheel20 defining a central plane 22 of the bicycle 10, and a frame 25. Theframe 25 has a head tube 30 and a front fork 35 that is rotationallysupported by the head tube 30 and that secures the front wheel 15 to theframe 25. A handlebar assembly 40 is coupled to the head tube 30 and issecured to the front fork 35 by a stem assembly 45 such that movement ofthe handlebar assembly 40 results in movement of the stem assembly 45and the fork 35.

With reference to FIGS. 1 and 2, the frame 25 also has a top tube 50connected to and extending rearward from the head tube 30, and a downtube 55 connected to the head tube 30 below the top tube 50 andextending generally downward toward and connected to a bottom brackethousing or shell 60 of the frame 25. A seat tube 65 extends upward fromthe bottom bracket shell 60 and is connected to the top tube 50, and aseat 70 is supported by the seat tube 65.

As shown in FIGS. 1-3, the down tube 55 is attached to the head tube 30by a connection tube 75 positioned between the head tube 30 and a downtube 55. As illustrated, one end of the connection tube 75 is shaped toconform to the contour of the head tube 30, and the other end of theconnection tube 75 abuts the down tube 55. The connection tube 75 iswelded to the head tube 30 and the down tube 55 to rigidly attach thedown tube 55 to the head tube 30. The illustrated connection tube 75also has cable ports 80 coupled to both sides of the connection tube 75.The connection tube 75 can be formed using a hydroforming process orother suitable manufacturing processes.

With reference to FIGS. 1-5 and 18, the bottom bracket shell 60 abutsand is welded to the down tube 55. The bottom bracket shell 60 alsoattaches the seat tube 65 and chain stays 85 to the remainder of theframe 25. The bottom bracket shell 60 has a kickstand mount 90 andbottom bracket mounts 95 that support a bottom bracket 100 (FIG. 1) toattach a drive train 105 to the bicycle 10. The bottom bracket shell 60is formed from aluminum by casting, although the shell 60 can be formedfrom other material (and a suitable manufacturing process).

The drive train 105 includes a crankset 110 that is rotatably mounted tothe bottom bracket 100. As shown in FIG. 1, the crankset 110 supportspedals 115 that are engageable by a rider to provide motive force forthe bicycle 10. The drive train 105 also includes a front derailleur 120that shifts a chain 125 between different chain rings 130 (one shown).The front derailleur 120 is actuated by a front shift controller 135 onthe handlebar assembly 40. A plurality of rear cogs 140 are mounted tothe rear wheel 20 and are connected to the crankset 110 by the chain125. A rear derailleur 145 shifts the chain 125 between different rearcogs 140 and is actuated by a rear shift controller 150 on the handlebarassembly 40.

FIGS. 6-9 show that the down tube 55 has an exterior surface 155 thatdefines an exterior cable groove 160, and a concave interior surface 165that defines a plurality of interior cable grooves 170. As illustratedin FIG. 6, the exterior cable groove 160 is recessed into a wall of thedown tube 55 and extends longitudinally along the underside of the downtube 55. With reference to FIGS. 4 and 5, the exterior cable groove 160is arcuate in cross-section and is centered along the underside of thedown tube 55.

Referring back to FIGS. 6-9, the interior cable grooves 170 are spacedlaterally relative to each other and are recessed into the wall of thedown tube 55. As illustrated, the down tube 55 has four interior cablegrooves 170 a-d that are arcuate in cross-section and that extendlongitudinally along the down tube 55. A first interior groove 170 a isspaced laterally relative to the vertical central plane 22 and has afirst groove width W1 and a first mouth 175 that is slightly narrowerthan the first groove width W1. A second interior groove 170 b islocated symmetrically opposite the first interior groove 170 a about thecentral plane 22. The second interior groove 170 b has a second groovewidth W2 and a second mouth 180 that is slightly narrower than thesecond groove width W2. As illustrated, the first and second groovewidth W1, W2 are approximately equal, although the widths can differ.

A third interior groove 170 c is spaced laterally inward relative to thefirst interior groove 170 a on one side of the central plane 22. Thethird interior groove 170 c has a third groove width W3 and a thirdmouth 185 that is slightly narrower than the third groove width W3. Afourth interior groove 170 d is spaced laterally inward relative to thesecond interior groove 170 b symmetrically opposite the third interiorgroove 170 c (i.e., on the other side of the central plane 22). Thefourth interior groove 170 d has a fourth groove width W4 and a fourthmouth 190 that is slightly narrower than the fourth groove width W4. Asillustrated, the third and fourth groove widths W3, W4 are approximatelyequal and larger than the first and second groove widths W1, W2,although the widths among the grooves 90 can differ.

With reference to FIG. 1, the bicycle 10 also includes front and rearbrake controllers 195, 200 that are attached to the handlebar assembly40 (as illustrated, the front brake controller 195 is positioneddirectly behind the rear brake controller 200 in FIG. 1). Optionally,each brake controller 195, 200 can include a switch (not shown) that isclosed when the brake controller 195, 200 is actuated. The front brakecontroller 195 is connected to a front brake 205 by a front brake cable210, and is routed directly to the front brake 205 along (e.g., throughor next to) the head tube 30 and the fork 35.

The rear brake controller 200 is connected to a rear brake 215 by a rearbrake cable 220. The rear brake cable 220 extends from the handlebarassembly 40 and along the bottom of the down tube 55 within the exteriorcable groove 160. The rear brake cable 220 is held in engagement withthe down tube 55 due to the opening of the groove 85 being slightlynarrower than the width of the cable 95. Also, as shown in FIGS. 13 and19, bolt-on clips 225 are attached to the down tube 55 to hold the rearbrake cable 220 in the exterior cable groove 160.

As illustrated, the rear brake cable 220 is a hydraulic brake cable thatassists with controlling the rear brake 215 and is routed within theexterior cable groove 160 to, among other things, avoid rupture duringassembly of the bicycle 10. In some cases, the exterior groove 160 cansupport cables for other bicycle components. Further, the size (e.g.,width, depth, diameter) of the exterior cable groove 160 can varydepending on the size of the cable routed in the groove 160.

With reference to FIGS. 3-5 and 19, the down tube 55 and the bottombracket shell 60 cooperatively define an entrance port 230 at the jointbetween the down tube 55 and the bottom bracket shell 60 so that therear brake cable 220 can be routed from the exterior of the down tube 55into the interior of the bottom bracket shell 60. In other words, theentrance port 230 provides a pathway for the rear brake cable 220 fromthe exterior of the down tube 55 to the interior of the bottom bracketshell 60. As shown in FIG. 5, the bottom bracket shell 60 has an accessopening 235 located along the underside of bottom bracket shell 60. Theaccess opening 235 provides access to the interior of the bottom bracketshell 60 so that the rear brake cable 220 can be easily routed throughthe shell 60 and one of the chain stays 85. A door 240 is detachablysecured (e.g., via fasteners, snap-fit arrangement, etc.) to the bottombracket shell 60 to cover the access opening 235.

With continued reference to FIGS. 1 and 6-9, the front shift controller135 is connected (e.g., electrically or mechanically) to the frontderailleur 120 by a first shift cable 245, and the rear shift controller150 is connected (e.g., electrically or mechanically) to the rearderailleur 145 by a second shift cable 250. As illustrated, the firstshift cable 245 is routed from the front shift controller 135 on thehandlebar assembly 40 through one of the cable ports 80 in theconnection tube 75 and is directed along the interior of the down tube55 within the first interior groove 170 a toward the bottom brackethousing 60. The bottom bracket shell 60 has an exit port 255 thatprovides a pathway from the interior of the shell 60 toward the locationof the front derailleur 120 on the seat tube 65. A cable guide 260 ispositioned in the exit port 255 to guide the first shift cable 245 fromthe bottom bracket shell 60 upward along the seat tube 65 toward thefront derailleur 120.

The second shift cable 250 is routed from the rear shift controller 150on the handlebar assembly 40 through another cable port 80 in theconnection tube 75. The second shift cable 250 is directed along theinterior of the down tube 55 within the second interior groove 170 btoward the bottom bracket housing 60. The second shift cable 250 extendsthrough the bottom bracket shell 60 and within one of the chain stays 85to the rear derailleur 145. The first and second shift cables 245, 250can be directed through the interior of the bottom bracket shell 60using the access opening 235.

As illustrated in FIG. 1, the bicycle 10 also includes a light cable 265that is connected to a light 270 mounted on the handlebar assembly 40.The light 270 can be integrated with an electrical circuit (not shown)of the bicycle 10 or provided as a stand-alone component. With referenceto FIGS. 7 a, 7 b, and 9, when the light 270 is integrated into theelectrical circuit of the bicycle 10, the light cable 265 is routed fromthe handlebar assembly 40 through a third cable port 80 and is directedalong the interior of the down tube 55 within the third interior groove170 c to a central power source and controller located on the bicycle10, as described in detail below. As illustrated in FIG. 7 b, the lightcable 265 has a cable width C1 that is less than the third groove widthW3.

With continued reference to FIGS. 1, 7 a, 7 b, and 9, the bicycle 10includes a bus cable 275 that interconnects one or more bicycle-mountedelectrical or electro-mechanical components (e.g., the front and rearshift controllers 135, 150, the front or rear brake controllers 195,200, the light, a remote 280 that is attached to the handlebar assembly40 or the stem assembly 45, a computer or data display, and/or otherelectrical or electro-mechanical devices such as an ANT+ device, a USBdevice, etc.) with the bicycle power source and controller. The buscable 275 is routed from the handlebar assembly 40 through a fourthcable port 80, and is then directed along the interior of the down tube55 within the fourth interior groove 170 d.

While the bicycle 10 is described in detail with regard to the exteriorand interior cables 220, 245, 250, 265, 275 routed in correspondinggrooves 85, 90, other cables can be routed along the down tube 55 inaddition or in lieu of the cables described herein. As illustrated inFIGS. 3, 7 a, 7 b, and 10, a cover 285 is attached to the interiorsurface 165 of the down tube 55 to provide a barrier between theinterior-routed cables 245, 250, 265, 275 and the interior of the downtube 55. Specifically, the cover 285 is placed over the interior cablegrooves 170 to hold the interior cables 245, 250, 265, 275 in positionand to protect the cables 245, 250, 265, 275 from, among other things,debris and abrasion. FIGS. 7 a and 7 b show that the cover 285 is curvedto conform to the concave interior surface 165 of the down tube 55.

With continued reference to FIGS. 7 a and 7 b, the cover 285 includes aprotrusion 290 that has a crescent-shaped cross-section and that isdimensioned to snap into the third interior groove 170 c to retain thecover 285 in position along the bottom wall of the down tube 55. Also,the protrusion 290 encapsulates or surrounds a portion of the lightcable 265 and holds the cable 265 in place within the third cable groovebecause the cable width C1 of the light cable 265 is smaller than thethird groove width W3. In this manner, the third interior groove 170 creceives the third cable and attaches the cover to the down tube 55.

Referring to FIGS. 2, 3, 7 a, 9, and 11-15, the bicycle 10 also includesa chargeport housing or receiver 295 and a battery pack 300 that arepositioned within the down tube 55, and a lock mechanism 305 that ispositioned within the bottom bracket shell 60 and in communication withthe receiver 295. The receiver 295 is positioned adjacent a forward oruppermost end of the down tube 55 and has an outer profile that conformsto the inner profile of the down tube 55. The illustrated receiver 295is secured in place within the down tube 55 by a fastener 310 (e.g.,mounting bolt) that engages a hole 315 in the side of the receiver 295.

The receiver 295 supports the electrical connections between thechargeport 335 and the battery pack 300. FIGS. 9, 10, and 13 show thatthe receiver 295 includes an axially aligned recessed area or taperedsocket 320 that is engageable by the battery pack 300. The taperedsocket 320 has a first electronics interface or power connector 325 thatis centered within the tapered socket 320. As illustrated, the powerconnector 325 is defined by a projection 330 with electrical contactslocated near the center of the projection 330. With reference to FIG.13, the power connector 325 is in electrical communication with achargeport 335 that is attached to the receiver 295 opposite thefastener 310. The chargeport 335 is accessible from outside the downtube 55 and has a socket 340 that receives a charger cable (not shown).The chargeport 335 is electrically connected to the battery pack 300 viathe power connector 325. The illustrated chargeport 335 is a pin-typeelectrical connector, although other types of electrical connectors arepossible. As shown in FIG. 1, a chargeport cover 345 encloses thechargeport 335 to protect it from debris, fluids, and other material towhich the down tube 55 may be exposed.

The battery pack 300 functions as the power source and controller forthe bicycle 10. Referring to FIGS. 2, 3, and 7 a, the battery pack 300is disposed in a compartment 350 in the down tube 55, although thebattery pack 300 can be supported in another tubular frame member (e.g.,the top tube 50, the seat tube 65, etc.) depending on the desiredlocation for the battery pack 300. The battery pack 300 is positioned inthe down tube 55 so that the battery pack 300 is physically separatedfrom the cables 245, 250, 265, 275 by the cover 285, and is furtherphysically separated from the rear brake cable 220 by the cover 285 andthe wall of the down tube 55. The receiver 295 is in communication withand accessible near an upper end of the compartment 350.

With reference to FIGS. 2, 3, 7 a, and 11-13, the battery pack 300defines a longitudinal axis 355 and includes an elongated shell orhousing 360 that is partially nested in the down tube 55 and thatsecurely supports one or more batteries 365 via inwardly directedsupport elements 370. In particular, the housing 360 has a lower portion375 that is formed to fit within the compartment 350, and an upperportion 380 that conforms to the exterior profile of the down tube 55.As illustrated in FIG. 6, the lower portion 375 is curved and has alower converging side surface 385 that are connected to an upperconverging side surface 390 of the upper portion 380 at longitudinalshoulders 395. A gasket or seal 400 is coupled to the housing 360 at thelongitudinal shoulders 395 (e.g., to dampen vibrations, or to inhibitinfiltration of debris, fluids, or other material into the compartment350). The battery pack 300 is recessed into down tube 55 such that thelongitudinal shoulders 395 rest on the edge of the compartment 350 andare located so that the housing 360 visibly blends into down tube 55.

As illustrated in FIG. 15, the housing 360 includes bottle cage mounts405 that are attached to the exposed upper surface 305. With referenceto FIGS. 1-3 and 15, a bottle cage 410 is mounted to the battery pack300 by fasteners 415 that engage threaded openings 420 in the cagemounts 320.

FIGS. 3 and 11-13 show that the battery pack 300 also has a powered endcap 425 coupled to the upper end of the housing 360, and an on/off orpower switch 430 located adjacent and electrically connected to the endcap 340. The power switch 430 can be either structurally attached to theend cap 340 or provided as a separate component on the battery pack 300.The illustrated power switch 430 includes a user interface or screen 435to communicate information (e.g., the state of charge of the batteries365) to a user.

The powered end cap 425 has a tapered protrusion 440 and a secondelectronics interface or battery connector 445 that is disposed on anend of the tapered protrusion 440. As illustrated, the battery connector445 has a recess 450 with electrical contacts located near the center ofthe recess 450. When the battery pack 300 is disposed in the down tube55, the tapered protrusion 440 is positioned within the tapered socket320 of the receiver 295 so that the projection 330 engages the recess450 to electrically connect the receiver 295 and the battery pack 300.The power connector 325 is detachably coupled to the battery connector445 due to the interface between the receiver 295 and the battery pack300 and the removability of the battery pack 300 from the down tube 55.

With reference to FIGS. 12 and 13, a lateral shoulder 455 is positionedbetween the upper converging side surface 390 of the housing 360 and thetapered protrusion 440. The protrusion 440 is substantially bull-nosedshaped and is partially defined by a continuously tapered surface 460.The tapered surface 460 has a conical taper adjacent the upper portion380 of the housing 360 and a curved taper opposite the conical taper(adjacent the lower portion 375 of the housing 360). In particular, theconical taper of the tapered surface 460 is curved in lateralcross-section (i.e., across or perpendicular to the longitudinal axis355) and is planar or straight in longitudinal cross-section (i.e.,along the longitudinal axis 355). As illustrated, the conical taper ofthe tapered surface 460 extends from the forward end of the powered endcap 425 toward the housing 360 and abuts the lateral shoulder 455. Thecurved taper is curved in both lateral cross-section and in longitudinalcross-section, and is substantially flush with the lower converging sidesurface 385 of the housing 360.

FIGS. 14 and 19 show a rearward end of the battery pack 300 thatincludes a securing end cap 465 enclosing the lower end of the housing360. As illustrated, the securing end cap 465 has an end surface 470that is oblique to the longitudinal axis 355, and a recess or opening475 in the end surface 470 that is engageable by the lock mechanism 305to secure the battery pack 300 in the down tube 55.

With reference to FIGS. 3 and 16-19, the lock mechanism 305 is locatedin the bottom bracket shell 60 such that the lock mechanism 305 isintegrated with the shell 60. The lock mechanism 305 is disposedadjacent the lower end of the battery pack 300 and includes a chassis480 with chassis bolts 485 that rigidly attach the lock mechanism 305 tochassis mounts inside the bottom bracket shell 60.

The lock mechanism 305 also includes a battery contact plate 490 and alatch assembly 495 that are attached to the bottom bracket shell 60 bythe chassis 480. The contact plate 490 is supported by and is movablerelative to the frame 25 into engagement with the securing end cap 465to support the battery pack 300. As illustrated, the contact plate 490has an oblique contact surface 500 facing the battery pack 300, and arearwardly-projecting post 505 that is engaged by a spring-biasedadjuster 510 to preload the contact plate 490. The adjuster 510 pushesthe contact plate 490 toward the down tube 55 so that when the batterypack 300 is inserted into the compartment 350, the securing end cap 465is engaged and pushed by the contact plate 490. In other words, thecontact surface 500 is biased into contact with the securing end cap465. The bias force of the contact surface 500 on the securing end cap465 is adjustable using an adjuster bolt 515 that is threaded into thepost 505. In this manner, the battery pack 300 is preloaded a desiredamount by the contact plate 490 to limit longitudinal movement of thebattery pack 300 within the down tube 55.

FIGS. 16-19 show the latch assembly 495 that is supported by the chassis480. The latch assembly 495 includes a latch 520 and a lock cylinder 525that is engaged with the latch 520 to lock and unlock the battery pack300 relative to the frame 25. The latch 520 is movable relative to thecontact plate 490 and has a locked position corresponding to a lockedstate of the lock mechanism 305, and an unlocked position correspondingto an unlocked state of the lock mechanism 305. The latch 520 is biasedto the locked position in which the latch 520 protrudes through a hole530 in the contact plate 490. The latch 520 is engaged with the opening475 in the securing end cap 465 to secure the battery pack 300 in theframe 25, and includes an outwardly (i.e., convex) end profile so thatthe battery pack 300 can be secured in the down tube 55 without havingto manually actuate the lock mechanism 305. In the unlocked position,the latch 520 is disengaged from the securing end cap 465 and issubstantially flush with the oblique surface 415 of the contact plate490 so that the battery pack 300 can be inserted or removed from thedown tube 55. In the illustrated embodiment, when the battery pack 300is latched into the down tube 55, movement of the latch 520 from thelocked position to the unlocked position can only be accomplished byturning the lock cylinder 525, as described below.

With reference to FIGS. 4 and 16-18, the lock mechanism 305 is movablebetween the locked state and the unlocked state using a key 535 that isengaged with the lock cylinder 525. As shown in FIG. 3, the lockcylinder 525 is accessible by a user through an aperture 540 in thebottom bracket shell 60. The lock cylinder 525 includes a lock housing545 and a plug 550 that has a keyway 555 with a predetermined key 535profile so that when the appropriate key 535 is inserted into the keyway555, the plug 550 can be rotated to move a cam-shaped lock lever 560.Movement of the lock lever 560 actuates the latch 520 between the lockedposition and the unlocked position.

The bicycle 10 also can include a motor (not shown) that is drivinglycoupled to the rear wheel 20 to selectively provide motive force for thebicycle 10 and/or to act as a generator for an electrical circuit (notshown) of the bicycle 10. The motor is electrically connected to andpowered by the battery pack 300, which can also serve as a controllerfor the motor and/or other electrical accessories on the bicycle 10.

After the frame 25 is assembled, the cables 220, 245, 250, 265, 275 arerouted from the handlebar assembly 40 through the down tube 55 and areenclosed by the cover 285. The receiver 295 is positioned in andattached to the down tube 55 via the fastener 310, and the lockmechanism 305 is positioned in and attached to the bottom bracket 60 viathe chassis bolts 485.

After the receiver 295 is attached to the down tube 55, the battery pack300 is secured to the down tube 55 by aligning the powered end cap 425with the tapered socket 320. With the powered end cap 425 so aligned,the battery pack 300 is nested in the compartment 350 by lowering thelower end of the battery pack 300 while at the same time lightly pushingthe battery pack 300 forward into engagement with the receiver 295. Thesecuring end cap 465 engages the contact plate 490, which is pushedslightly rearward (toward the bottom bracket shell 60) due to thepreload on the contact plate 490. The battery pack 300 is automaticallylocked in the down tube 55 upon full insertion into the compartment 350due to the outer profile of the biased latch 520. In embodiments that donot provide automatic locking of the battery pack 300 in the down tube55, the battery pack 300 can be manually locked in the down tube 55 bymoving the lock mechanism 305 to the locked state using the key 535.Because the battery pack 300 is firmly nested in the down tube 55, thebattery pack 300 is protected from damage along the underside of theframe 25 by the down tube 55. The chargeport 335 can be used to rechargethe batteries 365 without removing the battery pack 300 from the frame25.

The lock mechanism 305 is completely integrated into the frame 25 sothat all but the face of the lock cylinder 525 is visible on theexterior of the frame 25. The access opening 235 in the bottom bracketshell 60 provides access to the interior of the shell 60 so that thelock mechanism 305 can be assembled and maintained. Also, the cables220, 245, 250 (and other cables, as necessary) can be easily routed fromthe down tube 55 and through the bottom bracket shell 60 (e.g., towardthe seat tube 65 or the chain stays 85).

Various features and advantages of the invention are set forth in thefollowing claims.

The invention claimed is:
 1. A bicycle comprising: a frame including ahead tube; a fork rotationally coupled to the head tube; a wheelrotationally coupled to the fork; a handlebar coupled to the fork forsteering the wheel; a battery pack supported by the frame and defining alongitudinal axis, the battery pack including a powered end cap havingtapered protrusion with a portion that is curved in a longitudinalcross-section and a lateral cross-section and a battery connector on anend of the tapered protrusion; and a receiver supported by the frame andincluding a tapered socket in which the tapered protrusion ispositioned, the tapered socket including a power connector detachablycoupled to the battery connector, wherein the battery pack has a sidesurface and a shoulder between the side surface and the taperedprotrusion on at least one side of the battery pack, and wherein thetapered protrusion is bull-nosed shaped with a conical portion abuttingthe shoulder, and the portion that is curved is disposed opposite theconical portion.
 2. The bicycle of claim 1, wherein the battery pack hasa side surface and the tapered protrusion has a tapered surface that isflush with the side surface on at least one side of the battery pack. 3.A battery pack for a bicycle, the battery pack comprising: an elongatedhousing adapted to support a battery; and a powered end cap coupled tothe housing and having tapered protrusion with a portion that is curvedin a longitudinal cross-section and a lateral cross-section and abattery connector on an end of the tapered protrusion, the batteryconnector adapted to detachably couple to a power connector in thebicycle, wherein the housing has a side surface and the taperedprotrusion has a tapered surface that is flush with the side surface onat least one side of the battery pack, wherein the battery pack has ashoulder between the side surface and the tapered protrusion on at leastone side of the battery pack, and wherein the tapered protrusion isbull-nosed shaped with a conical portion abutting the shoulder and acurved portion opposite the conical portion.
 4. The battery pack ofclaim 3, wherein the powered end cap supports a power switch.
 5. Thebattery pack of claim 3, wherein the housing has a bottle cage support.6. The battery pack of claim 3, wherein the battery connector has arecess on the end of the tapered protrusion.
 7. The battery pack ofclaim 3, wherein the battery pack defines a longitudinal axis, andwherein the tapered protrusion has a tapered surface that is curved inlongitudinal cross-section.
 8. A bicycle comprising: a frame including ahead tube; a fork rotationally coupled to the head tube; a wheelrotationally coupled to the fork; a handlebar coupled to the fork forsteering the wheel; a battery pack supported by the frame, the batterypack including a securing end cap; a contact plate supported by andmovable relative to the frame, the contact plate including an openingand a contact surface that is biased into contact with the securing endcap; and a latch extending through the opening and movable relative tothe contact plate to secure the battery pack in the frame.
 9. Thebicycle of claim 8, wherein the battery pack defines a longitudinal axisand the securing end cap includes an end surface that is oblique to thelongitudinal axis.
 10. The bicycle of claim 9, wherein the contactsurface is oblique to the longitudinal axis and in contact with the endsurface.
 11. The bicycle of claim 8, wherein the bias force of thecontact surface is adjustable.
 12. The battery pack of claim 1, whereinthe tapered protrusion has a conical taper and a curved taper oppositethe conical taper.
 13. The battery pack of claim 3, wherein the taperedprotrusion has a conical taper and a curved taper opposite the conicaltaper.